Alkyl fluorohexahalogenoisopropoxycarboxylate silicon derivatives and polymers and copolymers thereof

ABSTRACT

THIS INVENTION IS ADDRESSED TO DERIVATIVES OF ALKYL FLUOROHEXAHALOGENOSIOPROPOXYCARBOXYLATE SILICON DERIVATIVES AND POLYMERS AND COPOLYMERS FORMED THEREOF. THE SILICON DERIVATIVES OF THE PRESENT INVENTION ARE USEFUL AS INTERMEDIATES IN THE PREPARATION OF SUCH POLYMERS AND COPOLYMERS WHICH ARE USEFUL AS LUBRICATNNTS, AS WATER REPELLENT AND OIL REPELLENT AGENTS AND AS SOLVENT RESISTANT FLUORINATED ELASTOMERS.

United States Patent 3 833,632 ALKYL FLUOROHEXAHALOGENOISOPROPOXY-CARBOXYLATE SILICON DERIVATIVES AND POLYMERS AND COPOLYMERS THEREOFFrangois Meiller, Palaiseau, France, assignor to Produits ChimiquesPechiney-Saint-Gobain, Neuilly-sur-Seine, France No Drawing. Originalapplication June 30, 1971, Ser. No. 158,614. Divided and thisapplication Jan. 4, 1973, Ser. No. 320,906 Claims priority, applicationFrance, July 6, 1970, 7024957 Int. Cl. C071 7/08 US. Cl. 260-4481 B 6Claims ABSTRACT OF THE DISCLOSURE This invention .is addressed toderivatives of alkyl fluorohexahalogenoisopropoxycarboxylate siliconderivatives and polymers and copolymers formed thereof. The siliconderivatives of the present invention are useful as intermediates in thepreparation of such polymers and copolymers which are useful aslubricants, as Water repellent and oil repellent agents and as solventresistant fluorinated elastomers.

This is a division of application Ser. No. 158,614, filed June 30, 1971.

This invention relates to alkyl fluorohexhalogenoisopropoxycarboxylatesilicon derivatives as well as their polymers and copolymers, and to aprocess for the preparation of such silicon derivatives, polymers andcopolymers.

It is known to prepare fiuoroalkoxyalkyl silanes, products possessing anether function, whose main use is the treatment of fibrous materials inorder to impart to them water repellent and oil repellent properties.

It is an object of this invention to produce and provide a method forproducing fluorinated silicon products possessing an ether function andwhich are useful in many fields.

According to this invention, the alkylfluorohexahalogenoisopropoxycarboxylate silicon derivatives arecompounds of the general formula:

wherein X X X X X g, and X';, represent a halogen atom, and preferably achlorine or a fluorine atom, with the provision that the number ofchlorine atoms of X X X X X' and X is 0, 1 or 2; n is an integer havinga value from 1 to 18; m is an integer having a value from 2 to 7; R Rand R are identical or difierent among themselves and represent eithernon-reactive groups, such as alkyl groups comprising for instance from 1to 3 carbon atoms (e.g., methyl, ethyl, isopropyl, etc.) or phenyl; orhydrolyzable groups, such as halogen atoms and preferably chlorineatoms, alkoxy groups Comprising from 1 to 3 carbon atoms (e.g., methoxy,ethoxy, propoxy, etc.), phenoxy or acyloxy comprising from 2 to 4 carbonatoms (e.g., acetoxy, propionoxy, butyryloxy, isobutyryloxy, etc.);moreover, one of the R R and R sub stituents can represent a hydrogenatom or a fluorohexahalogenoisopropoxycarboxyalkyl group in which thealkyl group contains 1 to 5 carbon atoms (e.g., isopropyl, butyl,methyl, ethyl, etc.); R represents an alkyl group conprising from 1 to 3carbon atoms (e.g., methyl, ethyl, propyl, etc.), a phenyl group or ahydrogen atom; R represents an alkyl group comprising from 1 to 3 carbonatoms (e.g., methyl, ethyl, propyl), a phenyl group or afiuorohexahalogenoisopropoxycarboxyalkyl group; q is an integer having avalue equal or above 1 and preferably a value from 1 to 6.

As illustrative of silicon derivatives corresponding to theabove-mentioned formula there can be cited for instance:

"ice

(heptafiuoroisopropoxyacetoxypropyl)- dimethylchloro silane,(heptafiuoroisopropoxyacetoxypropyl)- methyldichloro silane,(heptafiuoroisopropoxyacetoxypropyl)- trichloro silane,(hexafluorochloroisopropoxyacetoxypropyl)- methyldichloro silane,(heptafluoroisopropoxyacetoxyethyl) propyldichloro silane,(pentafluorodichloroisopropoxyacetoxyethyl)- phenyldichloro silane,(hexafluorochloroisopropoxybutyroxyhutyl)- phenylmethylchloro silane,bis (heptafluoroisopropoxyacetoxypropyl)- methylchloro silane,(pentafiuorodichloroisopropoxyacetoxyethyl) methylchloro silane,(hexafluorochloroisopropoxyacetoxypropyl)- phenylchloro silane,(heptafluoroisopropoxyacetoxybutyl)- dimethylmethoxy silane,(heptafluoroisopropoxyundecyloxyethyl)- methylphenylmethoxy silane,(heptafluoroisopropoxyacetoxypropyl methyldiethoxy silane,(heptafiuoroisopropoxyacetoxypropyl phenyldiethoxy silane,(hexafluorochloroisopropoxyacetoxyethyl)- phenylmethylethoxy silane,pentafluorodichloroisopropoxyacetoxyethyl)- triethoxy silane,(heptafluoroisopropoxyacetoxypropyl)- dimethylpropoxy silane,(heptafluoroisopropoxyacetoxypropyl)- phenyldiacetoxy silane,(heptafluoroisopropoxyacetoxypropyl)- heptamethylcyclotetrasiloxane,(pentafluorodichloroisopropoxyacetoxypropyl)-heptamethylcyclotetrasiloxane, heptafiuoroisopropoxyacetoxypropylnonamethylcyclopentasiloxane, heptafiuoroisopropoxyacetoxypropyl)-hexamethylcyclotetrasiloxane, bis(hexafluorochloroisopropoxyacetoxyethyl) hexamethylcyclotetrasiloxane,tris(pentafluorodichloroisopropoxyacetoxypropyl)-pentamethylcyclotetrasiloxane,tetrakis(heptafluoroisopropoxyacetoxypropyl)-tetramethylcyclotetrasiloxane,

pentakis (heptafluoroisopropoxyacetoxyethylpentamethylcyclopentasiloxane,

hexakis heptafluoroisop top oxyacetoxypropyl) hexaethylcyclohexasiloxane,

heptakis (heptafluoroisopropoxyacetoxypropyl)heptamethylcycloheptasiloxane,

tetrakis (hexafluoro chloroisopropoxyacetoxyethyloctamethylcyclohexasilox ane.

According to this invention, these silicon derivatives appear in theform of colorless liquids which are distillable when they are linear.

According to the process of preparation of alkylfluorohexahalogenoisopropoxycarboxylate silicon derivatives of thisinvention, there are reacted (a) a silane of the formula:

HSi R'; R's

or a cyclic siloxane of the formula:

R1 R4\ /Rs H-disio wherein R' R' R';, are identical or different amongthemselves and represent either nonreactive groups, such as alkyl groupscomprising from 1 to 3 carbon atoms (e.g., methyl, ethyl, isopropyl,etc), or phenyl; or hydrolyzable groups, such as halogen atoms and moreparticularly chlorine atoms, alkoxy groups comprising from 1 to 3 carbonatoms (e.g., methoxy, ethoxy, propoxy, etc.), phenoxy or acyloxycomprising from 2 to 4 carbon atoms (e.g.., acetoxy, propionoxy,butyryloxy, etc.); moreover, one or two of the R' R, and R' substituentscan represent a hydrogen atom, R and q have the same meaning as setforth above and R represents a hydrogen atom, an alkyl group comprisingfrom 1 to 3 carbon atoms (e.g., methyl, ethyl, isopropyl, etc.), or aphenyl group with (b) an alkylenefluorohexahalogenoisopropoxycarboxylate of the formula:

wherein X X X X' X'g, X' and n have the same meaning as set forth aboveand n is an integer having a value from 0 to 5.

The reaction is carried out in the presence of a catalyst at atemperature comprised between 30 and 120 C. and preferably between 50and 90 C.

Among the silanes and siloxaues which are reacted, the followingcompounds can be cited: methyldichloro silane, dimethylchloro silane,trichloro silane, propyldichloro silane, phenyldichloro silane,phenylmethylchloro silane, dimethylmethoxy silane, methylphenylmethoxysilane, phenylmethylethoxy silane, methyl diethoxy silane,phenyldiethoxy silane, triethoxy silane, phenyldiacetoxy silane,methylchloro silane, phenylchloro silane, methylethoxy silane,tetramethylcyclotetrasiloxane, pentamethylcyclopentasiloxane,hexamethylcyclohexasiloxane, heptamethylcycloheptasiloxane,pentamethylcyclotetrasiloxane, hexamethylcyclotetrasiloxane,heptamethylcyclotetrasiloxane, nonamethylcyclopentasiloxane,octamethylcyclohexasiloxane.

Alkylene fluorohexahalogenoisopropoxycarboxylates are prepared in aknown manner by reacting an alkylene halogenocarboxylate with thereaction product of a hexahalogenoacetone and an alkali metal fluoride.Thus, there are brought into contact in stoichiometric proportion, ahexahalogenoacetone of the formula: a r

Iii: Xr-(f-Xz i X'l-(E-X's X 2 wherein X X X X X and X' have the samemean ing as previously set forth and an alkali metal fluoride, andpreferably a fluoride represented by the fluorides of potassium, sodiumor cesium in a solvent, such as acetone, tetrahydrofuran, acetonitrile,dimethylformamide, diclyme, N-methylpyrrolidone, at room temperature, inan anhydrous medium and in the absence of all traces of oxygen. Thereaction is carried on until disappearance of the insoluble alkali metalfluoride in the reaction medium. Then, to the solution thus obtained,there is added an alkylene halogenocarboxylate of formula:

wherein n and n have the same meaning as previously set forth and Zrepresents an atom of chlorine, iodine or preferably an atom of bromine.Alkylene halogenocarboxylates are represented by vinyl iodoacetate,allyl bromoacetate, butenyl bromoacetate, allyl w-bromopropionate,butenyl bromobutyrate, vinyl w-bromoundecanoate, allylw-bromoundecanoate.

The reaction is carried out at a temperature comprised between roomtemperature and 100 C., and preferably between 40 and C. The reactiontime varies from 3 to 150 hours according to the reactivity of theproducts used. The alkylene fiuorohexahalogenoisopropoxycar: boxylateformed is separated either by centrifuging or kneading the alkali metalhalide formed and by evaporating the solvent or by treating the reactionmedium with water followed by decantation and drying of the product.When at all possible, the product can be distilled under reducedpressure. The yield ranges from 80 to Among the alkylenefluorohexahalogenoisopropoxycarboxylates, there can be cited allylheptafluoroisopropoxyacetate,

allyl hexafluorochloroisopropoxyacetate,

vinyl heptafluoroisopropoxyacetate,

vinyl hexafluorochloroisopropoxyacetate,

vinyl pentafluorodichloroisopropoxyacetate, allylpentafluorodichloroisopropoxyacetate, allylheptafluoroisopropoxypropionate, butenyl heptafluoroisopropoxyacetate,butenyl hexafiuorochloroisopropoxybutyrate, vinylheptafluoroisopropoxyundecanoate, allylhexafiuorochloroisopropoxyundecanoate.

The catalyst used in the method of preparation of the siliconderivatives of this invention is composed of chloroplatinic acid or analkali metal chloroplatinate and peroxides, such as diacetyl peroxide,benzoyl peroxide, tertiobutyl perbenzoate. The proportions of catalystused range from 1 to 10 p.p.rn. by weight of platinum based on thesilane for chloroplatinic derivatives, and from 13% by weight based onthe silane for peroxides.

Preferably the process is operated under atmospheric pressure, butaccording to the reactivity of the products, it may be operated underautogenous pressure. The reaction time ranges from 4-8 hours.

The silicon compound formed is then separated; the

light products which may have been formed during the reaction areeliminated and the silicon compound, if it is distillable, is submittedto a distillation. The yield ranges from 60-80%.

halogenocarboxyalkyl silane or a cyclic halogenocarboxyalkylsiloxanehaving respectively the formula:

wherein Z, R n, m and q have the same meaning as previously set forth,R" R" and R" identical or different among themselves represent eithernon-reactive groups, such as alkyl groups comprising from 1 to 3 carbonatoms (e.g., methyl, ethyl, isopropyl), or phenyl group, eitherhydrolyzable groups, such as alkoxy groups comprising from 1 to 3 carbonatoms (e.g., methoxy, ethoxy, propoxy, etc.); moreover, one of the R" R"or R substituents can be a hydrogen atom or a halogenocarboxyalkyl groupand R represents an alkyl group comprising from 1 to 3 carbon atoms(e.g., methyl, ethyl, isopropyl, etc.), a phenyl group or ahalogenocarboxyalkyl group.

The reaction is carried out at a temperature comprised between roomtemperature and 40 C. for reaction durations varying from to 150 hours,according to the reactivity of the products used.

Among the halogenocarboxyalkyl silanes and the cyclichalogenocarboxyalkyl siloxanes having the hereinabove mentionedformulae, the following compounds can be cited;

bromacetoxypropylmethyldiethoxy silane, bromacetoxypropylphenyldiethoxysilane, bromacetoxypropyldimethylethoxy silane,bromacetoxypropylmethyldimethoxy silane, bromacetoxypropyltriethoxysilane, bromacetoxypropyldimethylpropoxysilane,bromacetoxypropylphenylethoxysilane,bromacetoxyethylphenyldimethoxysilane,bromobutyroxybutylphenylmethylmethoxysilane,bromacetoxypentyltriethoxysilane, bromacetoxybutyldimethylmethoxysilane,bromacetoxyethylpropylethoxysilane,bromoacetoxyethylphenylmethylethoxysilanebromopropionoxypropylmethylethoxysilane,bromacetoXyethylmethylmethoxysilane, tetrakis (bromacetoxypropyl)tetramethylcyclotetra siloxane,bromacetoxypropyltetramethylcyclotetrasiloxane,bromacetoxypropylheptamethylcyclotetrasiloxane,bis(bromoacetoxypropyl)hexamethylcyclotetrasiloxane,bromacetoxypropylnonamethylcyclopentasiloxane,bromacetoxyethylpentamethylcyclopentasiloxane,bromacetoxyethylheptamethyldiphenylcyclopentasiloxane,bis(bromacetoxyethyl)octamethylcyclohexasiloxane, hexakis(bromacetoxypropyl) hexaethylcyclohexasiloxane, heptakis(bromacetoxypropyl )heptaethylcycloheptasiloxane.

The alkyl fluorohexahalogenoisopropoxycarboxylate silicon derivativesaccording to this invention are useful as intermediate products, andparticularly in the preparation of polymers and copolymers, byhydrolysis in the case of linear silanes, and by cycle rupture in thecase of cyclic siloxanes.

In the first case, according to the number of hydrolyzable substituentsattached to the silicon atom, polymers or copolymers having differentstructure and properties are obtained as follows: (1) If the siliconatom has a single hydrolyzable substituent, a dimer of the formula isobtained:

wherein each of R R and fluorohexahalogenoisopropoxycarboxy alkylsubstituents may be similar or different from a silicon atom to theother depending on whether a single silicon derivative or a mixture oftwo silicon derivatives of this invention is hydrolyzed. They areliquid, colorless and distillable products.

The silicon derivative can be cohydrolyzed with a conventional silanepossessing a hydrolyzable substituent and having the formula:

wherein R R and R are identical or different among themselves representa hydrogen atom, an alkyl group comprising from 1 to 3 carbon atom(e.g., methyl, ethyl, isopropyl, etc.), or a phenyl group and Rrepresents a halogen atom and more particularly a chlorine atom, analkoxy group comprising for instance from 1 to 3 carbon atoms (eig.,methoxy, ethoxy, propoxy, etc.), a phenoxy group or an acyloxy groupcomprising from 2 to 4 carbon atoms (e.g., acetoxy, propionoXy,butyryloxy, etc.). These conventional silanes are, for instance:dimethylchloro silane, trimethylchloro silane, diphenylchloro silane,phenyldimethylchloro silane, triethylmethoxy silane and trimethylacetoxysilane.

A mixed dimer having the following formula is then obtained:

These dimers are liquid, colorless and distillable products.

One or several silicon derivatives may also be cohydrolyzed with atleast a conventional silane possessing two hydrolyzable substituents andhaving the formula wherein R and R identical or different betweenthemselves have the same meaning as above, and R and R are identical ordilferent between themselves have the same meaning as that hereinabovementioned for R These conventional silanes are, for instance:methyldichloro silane, dimethyldichloro silane, phenyldichloro silane,phenylmethyldichloro silane, trifluoropropylmethyldichloro silane,phenyldiethoxy silane, diethyldimethoxysilane.

In this case, there is obtained a copolymer formed of a chain ofmonomeric units of the formula:

wherein each of the R R R and R andfluorohexahalogenoisopropoxycarboxyalkyl substituents may be similar ordifferent from one unit to the other according to whether there are oneor several silicon derivatives hydrolyzed with one or severalconventional silanes.

These copolymers are liquid, colorless products whose first terms aredistillable. (2) If the silicon atom possesses two hydrolyzablesubstituents, a linear polymer composed of a chain of monomeric units isobtained and having the formula:

wherein each of the R and fiuorohexahalogenoisoproproxycarboxyalkylsubstituents may be similar or different from one unit to the otheraccording to whether a single silicon derivative or a mixture of two orseveral silicon derivatives of this invention are hydrolyzed.

These polymers or copolymers are more or less viscous, colorless,nondistillable liquids.

One or several silicon derivatives may be cohydrolyzed with at least aconventional silane possessing two hydrolyzable substituents and havingthe formula Rg-Sfi-Rm R:

such as defined and cited hereinabove in (1).

The copolymer obtained is formed of a chain contaming monomeric units ofthe formulae ent from one unit to the other according to whether one orseveral silicon derivatives are hydrolyzed with'one or several standardsilanes.

The products obtained are more or less viscous, colorless,nondistillable liquids.

In order to obtain a more or less long chain of polymer or of copolymerof silanes having two hydrolyzable sub- 75,

wherein R R and R have the same meaning as previously, the disiloxanebeing represented, for instance, by hexamethylidisiloxane.

Chains of polymers or of copolymers having monomeric units such asrepresented hereinabove and endare thus obtained.

These polymers and copolymers containing chain lirniting agents are moreor less viscous liquids depending on the chain length, colorless, thefirst terms of which are distillable.

(3) If the silicon atom has thre hydrolyzable substituents, there isobtained a cross-linked polymer composed of monomeric units of formula:

X2 Xr-(il-Q'Ca OM F-- 0(OH2)n Co0-(CH2)m i-O X'1CX's 0.5

wherein each fluorohexah-alogenoisopropoxycarboxyalkyl group attached toa silicon atom may be similar or different from one unit to the otheraccording to whether a single silicon derivative or a mixture of severalsilicon derivatives of the invention are hydrolyzed.

One or several silicon derivatives having 3 hydrolyzable substituentsmay also be cohydrolyzed with at least one conventional silane having 3hydrolyzable subs-tituents and having the formula:

R1 Elifl-Rfl R12 wherein R represents a hydrogen atom, an 'alkyl groupcomprising from 1 to 3 carbon atoms (e.g., methyl, ethyl, isopropyl,etc.), a phenyl group, R R and R similar or different represent ahalogen atom, an alkoxy group comprising from 1 to 3 carbon atoms (e.g.,methoXy, ethoxy, propoxy, etc.), a phenoxy group, an acyloXy groupcomprising from 2 to 4 carbon atoms (e.g., acetoxy, propionoxy,butyryloxy, etc.).

As conventional silane having three hydrolyzable substituentsfthere canbe cited among other methyltrichloro silane, trichloro silane,phenyltrimethoxy silane, ethyltri! ethoxy silane, methyldichloromethoxysilane.

9 Cross-linked copolymers are hence obtained having monomeric units ofthe formula:

' 0.! Rr-f or besides the hereinabove represented monomeric units.

The polymers and copolymers thus formed are very viscous, low molecularweight, colorless and nondistillable liquids.

The hydrolysis of the silanes of this invention involves allowing toreact the silane or silanes with water at room temperature or withice-water possible in the presence of a solvent, then in neutralizingthe acid formed when the hydrolyzable substituent or substituents arehalogen atoms, in decantin and in separating the desired product.

The amount of water used is generally in excess of the theoreticalamount.

As possible solvents, products which dissolve the silane or silanes andthe polymer or copolymer formed are used. They are, for instance, ether,hexane, toluene, benzene, xylene and dioxane.

When an acid is formed, this latter is neutralized by addition ofdiluted or undiluted caustic soda, potash, sodium carbonate, potassiumcarbonate, sodium bicarbonate, ammonia water solutions.

In the case of cyclic siloxanes, by opening of the cycle, linearpolymers composed of monomeric unit chains are obtained of the formula:

wherein each of the R and fluorohexahalogenoisopropoxycarboxyalkylsubstituent may be similar or different from one unit to the otheraccording to whether a single cyclic siloxane or a mixture of severalcyclic siloxanes is used as starting material.

One or several cyclic siloxanes can be copolymerized with at least oneconventional cyclic siloxane having the formula:

1? R1{ i4 are 0Si o 0 /Si\O:|-Si\ LR13 Ru 1' R14 wherein R and R areidentical or different between themselves represent an alkyl groupcomprising from 1 to 3 carbon atoms (e.g., methyl, ethyl, isopropyl,etc.), a phenyl group, or a hydrogen atom and r is an integer having avalue from Oto 6. As conventional cyclic siloxane, the following may becited:

hexamethylcyclotrisiloxane,

octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane,tetramethylcyclotetrasiloxane, heptamethylcyclotetrasiloxane.

Copolymers having monomeric units are hence obtained of the formula:

R1: -o-s1- besides having also the hereinabove represented monomericunits. 1

These polymers and copolymers have very variable chain lengths accordingto the method of preparation employed.

Thus, when the cyclic siloxane or siloxanes are treated at roomtemperature with 10-15% of their Weight of an acid catalyst, thenneutralized, washed and dried, more or less viscous oils similar tothose described in (2) are obtained.

As acid catalyst, there can be cited sulphuric acid, boron fluoride, tintetrachloride, antimony pentachloride. Activated clays can also becited, but in this case the reaction is achieved at -140 C.

In order to modify the chain length, a chain limitating agent asrepresented either by a dimer or a mixed dimer according to thisinvention, or by a conventional linear disiloxane such as described in(2) can be added to the cyclic siloxanes.

On the other hand, when the cyclic siloxane or siloxanes are treated at130-170 C. for 2-8 hours, with 100 to 5000 ppm. by weight based on thesilicon atoms of a basic catalyst, then neutralized with carbon dioxidesnow, very high molecular translucent gums superior to 1,000,000 andwith a Williams plasticity of the order of are obtained.

The basic catalysts are represented by potash, caustic soda,tetramethylammonium hydroxide.

The present invention is also directed to the applications of theobtained polymers and copolymers.

Thus,\dimers and mixed dimers obtained from silanes having ahydrolyzable substituent are useful as chain limitating agents; polymersand copolymers having variable chain lengths, obtained from silaneshaving two hydrolyzable substituents or from siloxanes whose cycle isopened by means of an acid catalyst, are useful as lubricants having avariable viscosity; cross-linked polymers and copolymers obtained fromsilanes having three hydrolyzable substituents and more particularlythose which have a Si-H bond are useful as water-repellent andoilrepellent agents in the textile, paper and leather industries;polymers and copolymers in the form of gum, obtained from siloxaneswhose cycle is opened by means of a basic catalyst are useful as basematerial in the preparation of solvent-resistant fluorinated elastomersand having mechanical properties superior to those of conventionalsilicon elastomers.

Having described the basic concepts of the invention reference is nowmade to the following examples which are provided by way ofillustration, and not by way of limitation, of the practice of theinvention.

EXAMPLE 1 Preparation of (Heptafluoroisopropoxyacetoxypropyl)-Dimethylchloro Silane 8 g. of potassium fluoride and 200 g. of dryacetonitrile are introduced into a flask equipped with a stirrer and agas introduction pipe. A suspension is obtained in which a dry nitrogenflow is passed, then a dry gaseous hexafluoroacetone flow is passeduntil disappearance of the potassium fluoride. 24 g. ofhexafluoroacetone are then introduced. Then into the solution obtained,26 g. of allyl bromoacetate are added and the solution is heated to 60C., which is maintained for 10 hours. Afterwards, water is introduced,decanted and the product formed is dried and then distilled. It boils at60-65 C./ 20 mm. of

The 28 g. of allyl heptafluoroisopropoxyacetate obtained in which 5 ppm.of chloroplatinic acid has been dissolved (in an isopropanol solution)are introduced into a flask fitted with a stirrer and a liquidintroduction pipe. Air is drawn off by a nitrogen current and the flaskis heated at 80 C. Then 10 g. of dry dimethylchlorosilane are introducedat a speed such that the tempera- '11 ture is maintained at 80 C. Afterintroduction, this temperature is maintained for 1 hour.

By distillation at 901-08 C./ 18 mm. of Hg, 23 g. of a colorless liquidare collected, this representing a yield of 60%. i

The infrared analysis shows: two bands at 5.65;.t and 3 5.75;corresponding to C=O, a band at 12.5,u correspondingto -Si(CH and a bandat 21 1. corresponding to SiCl.

The elementary analysis gives the following results:

Calculated (percent): C, 31.70; H, 3.70; F, 35.15;.C1, 9.39. Found(percent): C, 31.84; H, 3.62; F, 34.8; Cl, 9.25.

Thus confirming the formula:

C F; CH8 F-(L-O-CH -G oo(oHr)ssi-o1 The product contains about 1% byweight of an isomer.

EXAMPLE 2 Polymerization of Hydrolysis of the Product of Example 1 Theproduct obtained in Example 1 is dissolved in 100 g. of ether, thenhydrolyzed by addition of 100 ml. of water.

The hydrochloric acid formed is neutralized by addition of sodiumbicarbonate, then the organic phase is decanted, dried, ether-evaporatedand distilled. 17 g. are collected, representing a yield of 80% of acolorless, odorless liquid which distills over at 160 C./ 15 mm. of Hg.

The elementary analysis gives the following results:

Calculated (percent): C, 34.28; H, 4; F, 38. Found (percent): C, 34.10;H, 3.75; F, 38.15.

Preparation of (Heptafluoroisopropoxyacetoxypropyl)- MethyldichloroSilane The same procedural steps as in Example 1 are employed but the g.of dimethylchloro silane are replaced by 12 g. of methyldichloro silane.

After distillation at 123 C./ 18 mm. of Hg, 25 g. of a colorless liquidslightly fuming in damp air are obtained representing a yield of 64%.

The infrared analysis shows: two bands at 5.65 1. and 5.75 1corresponding to -C=O, a band at 12.4;1; corresponding to SiCH a band at18.6;1. corresponding to Si--Cl and a group of bands at 8-9ucorresponding to CF.

The elementary analysis gives the following results:

Calculated (percent): C, 27.07; H, 2.75; F, 33.33; Cl, 17.75. Found(percent): C, 27.2; H, 2.7; F, 33.45; Cl, 17.6.

Thus confirming the formula:

CF; 01 FCO-CHz-COO(CHz)al-CH:

EXAMPLE 4.

Polymerization by Hydrolysis of the Product of Example 3 The productobtained in Example 3 is dissolved 100 ml. of ether, then hydrolyzedwith 150 ml. of water.

After neutralization, decantati0n,,,d rying and eyaporation CH3 I st-91"r'to-c-org EXAMPLE 5 I Preparation of(Heptafluoroisopropoxyacetoxypropyl) Trichloro- Silane Example 1 isrepeated, but with 14g. of trichloro silane instead of the 10 g. ofadimethylchloro silane.1

After distillation at 132136 -C./22 mm. of Hg, 28g. of a colorlessliquid are-obtained, fumingin 'dampair and representing a yield of 65The infrared analysis shows: two bands of 5.65 and 5.75; correspondingtoO=O, a doublebond at 16911.4 and 17.7 corresponding to -SiCl a groupof bands .at 89u corresponding to C-F.

The elementary analysis gives the following results:

Calculated (percent) 5 C, 22.85; H, 1.92; F, 31.8; C1, 25.40. Found(percent): C, 22.70; H, 2.05; F, 31.9; C1, 25.30.

Thus corresponding to the formula:

The product contains a very small quantity of an isomer.

EXAMPLE 6 Polymerization by Hydrolysis of the Product of j Example 5 i fThe product obtained in Example 5 ishydrolyzed in the same manner as inExample 4.

A cross-linked liquid polymer is obtained which has a viscosity of 5,000centistokes at 20 C. and is composed of monomeric units having theformula EXAMPLE 7 Preparation of Hexafluorochloroisopropoxyacetoxypropyl) Methyldichloro Silane" 13 EXAMPLE 8 The following materials aremixed: 29.1 g. of the product obtained in Example 7, 24.2 g. ofmethydichloro silane, 2.28 g. of hexamethyldisiloxane and 100 ml. ofhexane.

The mixture is then' poured on ice under agitation, followed by itsdecantation, neutralization with sodium bicarbonate, washing with water,drying and evaporation of hexane.

40 g. of a colorless oil representing a yield of 85% are obtained.

The infrared analysis shows: a band at 4.6 corresponding to --'Si-H, twobands at 5.6g. and 5.72; corresponding to C=O, a group of bands between8, and 8.7 1. corresponding" to -F, and a group of bands between 9, and9.551. corresponding to SiOSi-.

The product is composed of a chain having monomeric units of formulae:

pm --Si O FaC-(IJ-C FaCl Preparation of(Heptailuoroisopropoxyacetoxypropyl) Methyldiethoxy Silane As describedin Example 1, 16.6 g. of potassium fluoride are reacted with 43 g. ofhexafiuoroacetone in 165 ml. of acetonitrile.

313 g. of bromoacetoxypropyl-methyl-diethoxy silane of formula:

Br-OIL-C O0-(CHz)3-S 1-(0 C2115):

are then added.

The mixture is allowed to stand for a day at room temperature, then for15 days at 40 C.

The potassium bromide formed is then filtered, the acetonitrile isdistilled, then the product formed at 142 C./ mm. of Hg whichcorresponds to the formula:

300 g. of product are obtained, that is to say, a yield of 72%.

14 The gas chromatography analysis shows that the product contains alittle of the initial brominated product, about 2%.

EXAMPLE 10 Polymerization by Hydrolysis of the Product of Example 9 The300 g. of the product obtained in Example 9 are dissolved in 600 m1. ofether, then hydrolyzed with 600ml. of water. After neutralization byaddition of sodium bicarbonate, decantation, drying and evaporation ofthe ether, 220 g. of a colorless and odorless oil are obtained andcomposed of a chain of monomeric units having the formula:

This oil has a viscosity of 170 centistokes at 20 C. and is practicallyidentical to that of Example 4.

EXAMPLE 11 Preparation of Tetrakis(Heptafluoroisopropoxyacetoxypropyl')Tetramethylcyclotetrasiloxanecorresponding to -CF and superposing a group of bands corresponding toSi-O Si.

Thus, confirming the formula:

EXAMPLE 12 Polymerization of the Product of Example 7 by Rupture of theRing 344 g. of the product of Example 11 are introduced into a vesselhaving a wide opening, fitted with a very efiicient stirrer. Theapparatus is flushed out by means of a current of nitrogen, then heatedto C. 0.05 g. of finely crushed potash is then added and maintained at160 C. for 6 hours. The polymerization is then over. A gum is obtainedwhich is neutralized with carbon dioxide snow as a sigmatype blademixer.

15 The gum has a Williams plasticity of 150. It is composed of a chainof monomeric units having the formula:

It will be understood that various changes and modifications may be madein the procedure, formulation and use without departing from the spiritof the invention, especially as defined in the following claims.

I claim:

1. Alkyl fluorohexahalogenoisopropoxycarboxylate silicon derivativesrepresented by the formula wherein X X X X' X' X' represent a halogenatom with the provision that the number of chlorine atoms of X X X X' X'and X;, is 0, 1 or 2; n is an integer having a value from 1 to 18; m isan integer having a 'value from 2 to 7; R represents an alkyl groupcontaining 1 to 3 carbon atoms, a phenyl group or a hydrogen atom; Rrepresents an alkyl group containing 1 to 3 carbon atoms, a phenyl groupor a fluorohexahalogenoisopropoxycarboxyalkyl group in which the alkylcontains 1 to 5 carbon atoms; and q is an integer having a value equalto or superior to 1.

2. Silicon derivatives as defined in claim 1 wherein X X X X' X' and X;,are each selected from the group consisting of fluorine and chlorineatoms.

3. Silicon derivatives as defined in claim 1 wherein q is an integerfrom 1 to 6.

4. Process for the preparation of silicon derivatives according to claim1 comprising reacting (a) a cyclic siloxane of the formula wherein R andq have the samelmeaning as in claim/ and R' represents a hydrogen atom,an alkyl group com-- prising from 1 to 3 carbon atoms or a phenyl group,with (b) an alkylene -fluorohexahalogenoisopropoxycar boxylate of theformula 1 4 J References Cited UNITED STATES PATENTS 3,478,076 11/1969et al. 260448.2 B 3,45 8,554 7/ 1969 Haluska 260448.2 B

3,560,542 2/1971 Kim'et a1. 260448.2B

DANIEL E. WYMAN, PrimaryExaminer P. E. SHAVER, Assistant ExaminerU.S.,C1 .X.R,

25249.6; 260448.2 E, 1465 G a v UNITED STATES PATENT OFFICE CERTIFICATEOF CQRRECTION Pat nt No. 3,833,632 Dated September L 1974 Inventor(s)Francois MEILLER' It is certified that error appears in theabove-identified patent and the; said Letters Patent are herebycorrected as shown below:

IN THE SPECIFICATION In columnl, line 58, in the formula, the middle "R"should be R e- In column 8, line 39, thre" should read three Signedand-sealed this 3rd day of December 19-74..

(SEAL) Attest;

McCOY M. GIBSON JR. c. MARSHALL DANN Attesting Officer Conunissioner ofPatents

